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Lisbeth Wellejus Albertsen,1 Uffe Heide-Jørgensen,1 Sigrun Alba Johannesdottir Schmidt,1 Corina Grey,2 Rod Jackson,2 Henrik Toft Sørensen,1 Morten Schmidt1,3,4 1Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark; 2Section of Epidemiology and Biostatistics, School of Population Health, University of Auckland, Auckland, New Zealand; 3Department of Cardiology, Regional Hospital West Jutland, Herning, Denmark; 4Department of Cardiology, Aarhus University Hospital, Aarhus, DenmarkCorrespondence: Morten Schmidt Email Morten.schmidt@clin.au.dkObjective: To develop and validate the DANish Comorbidity index for Acute Myocardial Infarction (DANCAMI) for adjustment of comorbidity burden in studies of myocardial infarction prognosis.Methods: Using medical registries, we identified patients with first-time myocardial infarction in Denmark during 2000– 2013 (n=36,685). We developed comorbidity indices predicting 1-year all-cause mortality from all comorbidities (DANCAMI) and restricted to non-cardiovascular comorbidities (rDANCAMI). For variable selection, we eliminated comorbidities stepwise using hazard ratios from multivariable Cox models. We compared DANCAMI/rDANCAMI with Charlson and Elixhauser comorbidity indices using standard performance measures (Nagelkerke’s R2, Harrell’s C-statistic, the Integrated Discrimination Improvement, and the continuous Net Reclassification Index). We assessed the significance of the novel DANCAMI variables not included in the Charlson Comorbidity Index. External validation was performed in patients with myocardial infarction in New Zealand during 2007– 2016 (n=75,069).Results: The DANCAMI included 24 comorbidities. The rDANCAMI included 17 non-cardiovascular comorbidities. In the Danish cohort, the DANCAMI indices outperformed both the Charlson and the Elixhauser comorbidity indices on all performance measures. The DANCAMI indices included multiple variables that were significant predictors of 1-year mortality even after controlling for all variables in the Charlson Comorbidity Index. These novel variables included valvular heart disease (hazard ratio for 1-year mortality=1.25, 95% CI: 1.14– 1.35), coagulopathy (1.13, 95% CI: 1.05– 1.22), alcohol and drug abuse (1.35, 95% CI: 1.15– 1.58), schizophrenia (1.60, 95% CI: 1.46– 1.76), affective disorder (1.29, 95% CI: 1.22– 1.36), epilepsy (1.26, 95% CI: 1.05– 1.50), neurodegenerative disorder (1.30, 95% CI: 1.10– 1.54) and chronic pancreatitis (1.71, 95% CI: 1.14– 2.56). The results were supported by the external validation in New Zealand.Conclusion: DANCAMI assessed comorbidity burden of patients with first-time myocardial infarction, outperformed existing comorbidity indices, and was generalizable to patients outside Denmark. DANCAMI is recommended as a standard approach for comorbidity adjustment in studies of myocardial infarction prognosis.Keywords: comorbidity, myocardial infarction, prognosis, risk score

El progresivo aumento en los precios del petróleo y el agotamiento de sus reservas ha motivado a la sociedad científica a pensar en combustibles alternativos y renovables como el biodiesel. La producción de biodiesel se lleva a cabo principalmente por transesterificación de triacilglicéridos (aceites vegetales y grasas animales) y un alcohol liviano en presencia de catalizadores. Los catalizadores homogéneos tipo hidróxidos de sodio o de potasio son típicamente los más empleados en la producción de biodiesel; desafortunadamente problemas asociados principalmente con el aumento de costos debido a la implementación de etapas de separación y el tratamiento posterior de aguas residuales, ha enfocado la atención de los investigadores hacia el empleo de catalizadores heterogéneos. Este artículo presenta una revisión sobre tres tipos de catalizadores heterogéneos, los óxidos de metales alcalinotérreos, las zeolitas y los heteropoliácidos, empleados en reacciones de transestrificación de aceites para la obtención de biodiesel. En términos generales, estos catalizadores han demostrado ser eficientes, selectivos, fáciles de separar, reutilizables y algunos más que otros, tolerables a la presencia de agua y de ácidos grasos libres.

Zinc metal batteries (ZMBs) are promising candidates for low-cost, intrinsically safe, and environmentally friendly energy storage systems. However, the anode is plagued with problems such as the parasitic hydrogen evolution reaction, surface passivation, corrosion, and a rough metal electrode morphology that is prone to short circuits. One strategy to overcome these issues is understanding surface processes to facilitate more homogeneous electrodeposition of zinc by guiding the alignment of electrodeposited zinc. Using Scanning Electrochemical Microscopy (SECM), the charge transport rate on zinc metal anodes was mapped, demonstrating that manipulating electrolyte concentration can influence zinc electrodeposition and solid electrolyte interphase (SEI) formation in ZMBs. Using XPS and Raman spectroscopy, it is demonstrated that an SEI is formed on zinc electrodes at neutral pH, composed primarily of a Zn4(OH)6SO4·xH2O species, its formation being attributed to local pH increases at the interface. This work shows that more extended high-rate cycling can be achieved using a 1 M ZnSO4 electrolyte and that these systems have a reduced tendency for soft shorts. The improved cyclability in 1 M ZnSO4 was attributed to a more homogeneous and conductive interface formed, rather than the bulk electrolyte properties. This experimental methodology for studying metal battery electrodes is transferable to lithium metal and anode-free batteries, and other sustainable battery chemistries such as sodium, magnesium, and calcium. [ABSTRACT FROM AUTHOR]

Correction for 'The effect of interface heterogeneity on zinc metal anode cyclability' by J. T. Simon et al., J. Mater. Chem. A, 2024, DOI: https://doi.org/10.1039/d4ta03165b. [ABSTRACT FROM AUTHOR]

BACKGROUND: To determine the clinical implications and gestation age-specific diagnostic predictability of pneumatosis in preterm infants with necrotizing enterocolitis (NEC). METHODS: A retrospective study on abdominal radiographs comparing clinical and radiological information in infants with and without pneumatosis. RESULT: Our findings disproved our hypothesis. Pneumatosis was seen more frequently in infants with higher gestational age [28.4 (26.1–32.4) vs. 26.4 (24.3–29) weeks; p < 0.001] and birth weight [1110 (762–1768) vs. 770 (645–1022) grams; p < 0.001] and were more likely delivered vaginally (39.1% vs. 21.7%, p = 0.01). Portal venous gas was seen frequently on radiographs (10.3% vs. 0%, p < 0.001), but not pneumoperitoneum (20.7% vs. 36.7%, p = 0.02). Infants with pneumatosis frequently developed acute kidney injury, with higher serum creatinine (16.5% vs. 4.5%, p = 0.02) and frequent oliguria (12.9% vs. 2.7 %; p = 0.043) and had higher C-reactive protein levels at 24 and 96 hours (p < 0.002). Receiver operating curves for pneumatosis showed GA >28 weeks and birth weight > 1000 gm to have a sensitivity of 58.6% and specificity of 72.5%. CONCLUSION: Contrary to our hypothesis, infants who developed pneumatosis during NEC were more mature with a higher gestational age and birth weight than those who did not. [ABSTRACT FROM AUTHOR]

Infrared-active optical phonons were studied in olivine LiFePO4 oriented single crystals by means of both rotating analyzer and rotating compensator spectroscopic ellipsometry in the spectral range between 50 and 1400 cm-1. The eigenfrequencies, oscillator strengths, and broadenings of the phonon modes were determined from fits of the anisotropic harmonic oscillator model to the data. Optical phonons in a heterosite FePO4 crystal were measured from the delithiated ab-surface of the LiFePO4 crystal and compared with the phonon modes of the latter. Good agreement was found between experimental data and the results of solid-state hybrid density functional theory calculations for the phonon modes in both LiFePO4 and FePO4. [ABSTRACT FROM AUTHOR]

The effect of long-term (1 y) low to excess ascorbic acid (AA) intake on bone mass was evaluated using guinea pigs that were 12-14 d old at the start of the experiment. Dietary AA was low (0.15 g/kg diet) (n = 7), normal (0.50 g/kg) (n = 8) or excess (10 g/kg) (n = 8). After 12 mo, total body bone mineral density (BMD, mg/[cm.sup.2]) and bone mineral content (BMC, g) were determined by dual energy X-ray absorptiometry. Histomorphometric analysis of the cancellous bone of the proximal tibial metaphysis was completed after in vivo dual fluorochrome labeling. Total body BMD of the low AA group was 4.9% lower (P [less than] 0.05), and total body BMC was 12.4% lower (P [less than] 0.05) than in the normal AA group. Total body BMD and BMC were similar in normal and excess AA groups and in the low and excess AA groups. Histomorphometric analysis indicated significantly greater (P [less than] 0.05) double-labeled bone surface, mineralizing surface, and bone formation rate in the low AA guinea pigs compared with the normal AA animals. Thus, there was greater bone turnover in the low AA group than in the normal AA guinea pigs. No differences in histomorphometric endpoints existed between the normal AA and excess AA groups. Long-term AA deficiency, during the period of rapid growth and slower phases of skeletal maturation, resulted in bone abnormalities in adult guinea pig skeletons. Long-term dietary AA excess caused no such abnormalities. J. Nutr. 126: 2044-2049, 1996. INDEXING KEY WORDS: guinea pigs; ascorbic acid; bone mass; densitometry; histomorphometry

Average monthly global radiation in Jamaica was calculated for the years between 1978 and 1987 from values measured at 12 stations and from Angstrom-coefficient derived values. From these values daily global radiation was estimated for various periods at grid points separated by approximately 10 km on a square. Three dimensional plots and contour maps for the various periods were produced. The interpolation was based on kriging adopted by Hay (1986). A relationship between global and diffuse radiation based on the Liu and Jordan (1960) relationship was obtained. The errors in the interpolated annual values were less than 10%. The maps were made available to the public with suggested usages of solar energy. Diffuse radiation formed less than 50% of the total radiation.